Abstract: This essay provides a brief description of the history and a new version of unified field theory. It starts from ancient Greek and Chinese philosophers’inspirations and goes down to the modern era. After completion of general relativity, Einstein spent rest of his life search for unified field theory without success. Since 1970s, a new generation of physicists involved. The spring theory is based on quantum theory and multidimensional space. The loop theory is based on general relativity with background independence. After thousands of talented physicists and mathematicians forty some years of extensive effort, the unified field theory is still far of reach. Now is the time for a second thought. The author spent eight years to develop a unified field theory entitled “A New Version of Unified Field Theory—Stochastic Quantum Space Theory on Particle Physics and Cosmology” published in Journal of Modern Physics, 2013, Vol. 4, No. 10, pp. 1213-1380. The Stochastic Quantum Space (SQS) theory based on simple postulations builds a framework with dozens of theoretical results agreed with experiments well. It has 25 predictions for verifications. SQS theory provided the basic equations for unified field theory, which are based on general relativity Einstein’s equation for vacuum and redefined the gauge tensor by multiplying Gaussian probability. The preliminary analysis for photon and electron shows reasonable agreement with experiments.